xref: /linux/drivers/sh/intc/core.c (revision a1087ef6abedf0bfd60e5e3fddf33192cb2c1325)
1 /*
2  * Shared interrupt handling code for IPR and INTC2 types of IRQs.
3  *
4  * Copyright (C) 2007, 2008 Magnus Damm
5  * Copyright (C) 2009, 2010 Paul Mundt
6  *
7  * Based on intc2.c and ipr.c
8  *
9  * Copyright (C) 1999  Niibe Yutaka & Takeshi Yaegashi
10  * Copyright (C) 2000  Kazumoto Kojima
11  * Copyright (C) 2001  David J. Mckay (david.mckay@st.com)
12  * Copyright (C) 2003  Takashi Kusuda <kusuda-takashi@hitachi-ul.co.jp>
13  * Copyright (C) 2005, 2006  Paul Mundt
14  *
15  * This file is subject to the terms and conditions of the GNU General Public
16  * License.  See the file "COPYING" in the main directory of this archive
17  * for more details.
18  */
19 #define pr_fmt(fmt) "intc: " fmt
20 
21 #include <linux/init.h>
22 #include <linux/irq.h>
23 #include <linux/io.h>
24 #include <linux/slab.h>
25 #include <linux/interrupt.h>
26 #include <linux/sh_intc.h>
27 #include <linux/sysdev.h>
28 #include <linux/list.h>
29 #include <linux/spinlock.h>
30 #include <linux/radix-tree.h>
31 #include "internals.h"
32 
33 LIST_HEAD(intc_list);
34 DEFINE_RAW_SPINLOCK(intc_big_lock);
35 unsigned int nr_intc_controllers;
36 
37 /*
38  * Default priority level
39  * - this needs to be at least 2 for 5-bit priorities on 7780
40  */
41 static unsigned int default_prio_level = 2;	/* 2 - 16 */
42 static unsigned int intc_prio_level[NR_IRQS];	/* for now */
43 
44 unsigned int intc_get_dfl_prio_level(void)
45 {
46 	return default_prio_level;
47 }
48 
49 unsigned int intc_get_prio_level(unsigned int irq)
50 {
51 	return intc_prio_level[irq];
52 }
53 
54 void intc_set_prio_level(unsigned int irq, unsigned int level)
55 {
56 	unsigned long flags;
57 
58 	raw_spin_lock_irqsave(&intc_big_lock, flags);
59 	intc_prio_level[irq] = level;
60 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
61 }
62 
63 static void intc_redirect_irq(unsigned int irq, struct irq_desc *desc)
64 {
65 	generic_handle_irq((unsigned int)get_irq_data(irq));
66 }
67 
68 static void __init intc_register_irq(struct intc_desc *desc,
69 				     struct intc_desc_int *d,
70 				     intc_enum enum_id,
71 				     unsigned int irq)
72 {
73 	struct intc_handle_int *hp;
74 	struct irq_data *irq_data;
75 	unsigned int data[2], primary;
76 	unsigned long flags;
77 
78 	/*
79 	 * Register the IRQ position with the global IRQ map, then insert
80 	 * it in to the radix tree.
81 	 */
82 	irq_reserve_irqs(irq, 1);
83 
84 	raw_spin_lock_irqsave(&intc_big_lock, flags);
85 	radix_tree_insert(&d->tree, enum_id, intc_irq_xlate_get(irq));
86 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
87 
88 	/*
89 	 * Prefer single interrupt source bitmap over other combinations:
90 	 *
91 	 * 1. bitmap, single interrupt source
92 	 * 2. priority, single interrupt source
93 	 * 3. bitmap, multiple interrupt sources (groups)
94 	 * 4. priority, multiple interrupt sources (groups)
95 	 */
96 	data[0] = intc_get_mask_handle(desc, d, enum_id, 0);
97 	data[1] = intc_get_prio_handle(desc, d, enum_id, 0);
98 
99 	primary = 0;
100 	if (!data[0] && data[1])
101 		primary = 1;
102 
103 	if (!data[0] && !data[1])
104 		pr_warning("missing unique irq mask for irq %d (vect 0x%04x)\n",
105 			   irq, irq2evt(irq));
106 
107 	data[0] = data[0] ? data[0] : intc_get_mask_handle(desc, d, enum_id, 1);
108 	data[1] = data[1] ? data[1] : intc_get_prio_handle(desc, d, enum_id, 1);
109 
110 	if (!data[primary])
111 		primary ^= 1;
112 
113 	BUG_ON(!data[primary]); /* must have primary masking method */
114 
115 	irq_data = irq_get_irq_data(irq);
116 
117 	disable_irq_nosync(irq);
118 	set_irq_chip_and_handler_name(irq, &d->chip,
119 				      handle_level_irq, "level");
120 	set_irq_chip_data(irq, (void *)data[primary]);
121 
122 	/*
123 	 * set priority level
124 	 */
125 	intc_set_prio_level(irq, intc_get_dfl_prio_level());
126 
127 	/* enable secondary masking method if present */
128 	if (data[!primary])
129 		_intc_enable(irq_data, data[!primary]);
130 
131 	/* add irq to d->prio list if priority is available */
132 	if (data[1]) {
133 		hp = d->prio + d->nr_prio;
134 		hp->irq = irq;
135 		hp->handle = data[1];
136 
137 		if (primary) {
138 			/*
139 			 * only secondary priority should access registers, so
140 			 * set _INTC_FN(h) = REG_FN_ERR for intc_set_priority()
141 			 */
142 			hp->handle &= ~_INTC_MK(0x0f, 0, 0, 0, 0, 0);
143 			hp->handle |= _INTC_MK(REG_FN_ERR, 0, 0, 0, 0, 0);
144 		}
145 		d->nr_prio++;
146 	}
147 
148 	/* add irq to d->sense list if sense is available */
149 	data[0] = intc_get_sense_handle(desc, d, enum_id);
150 	if (data[0]) {
151 		(d->sense + d->nr_sense)->irq = irq;
152 		(d->sense + d->nr_sense)->handle = data[0];
153 		d->nr_sense++;
154 	}
155 
156 	/* irq should be disabled by default */
157 	d->chip.irq_mask(irq_data);
158 
159 	intc_set_ack_handle(irq, desc, d, enum_id);
160 	intc_set_dist_handle(irq, desc, d, enum_id);
161 
162 	activate_irq(irq);
163 }
164 
165 static unsigned int __init save_reg(struct intc_desc_int *d,
166 				    unsigned int cnt,
167 				    unsigned long value,
168 				    unsigned int smp)
169 {
170 	if (value) {
171 		value = intc_phys_to_virt(d, value);
172 
173 		d->reg[cnt] = value;
174 #ifdef CONFIG_SMP
175 		d->smp[cnt] = smp;
176 #endif
177 		return 1;
178 	}
179 
180 	return 0;
181 }
182 
183 int __init register_intc_controller(struct intc_desc *desc)
184 {
185 	unsigned int i, k, smp;
186 	struct intc_hw_desc *hw = &desc->hw;
187 	struct intc_desc_int *d;
188 	struct resource *res;
189 
190 	pr_info("Registered controller '%s' with %u IRQs\n",
191 		desc->name, hw->nr_vectors);
192 
193 	d = kzalloc(sizeof(*d), GFP_NOWAIT);
194 	if (!d)
195 		goto err0;
196 
197 	INIT_LIST_HEAD(&d->list);
198 	list_add_tail(&d->list, &intc_list);
199 
200 	raw_spin_lock_init(&d->lock);
201 
202 	d->index = nr_intc_controllers;
203 
204 	if (desc->num_resources) {
205 		d->nr_windows = desc->num_resources;
206 		d->window = kzalloc(d->nr_windows * sizeof(*d->window),
207 				    GFP_NOWAIT);
208 		if (!d->window)
209 			goto err1;
210 
211 		for (k = 0; k < d->nr_windows; k++) {
212 			res = desc->resource + k;
213 			WARN_ON(resource_type(res) != IORESOURCE_MEM);
214 			d->window[k].phys = res->start;
215 			d->window[k].size = resource_size(res);
216 			d->window[k].virt = ioremap_nocache(res->start,
217 							 resource_size(res));
218 			if (!d->window[k].virt)
219 				goto err2;
220 		}
221 	}
222 
223 	d->nr_reg = hw->mask_regs ? hw->nr_mask_regs * 2 : 0;
224 #ifdef CONFIG_INTC_BALANCING
225 	if (d->nr_reg)
226 		d->nr_reg += hw->nr_mask_regs;
227 #endif
228 	d->nr_reg += hw->prio_regs ? hw->nr_prio_regs * 2 : 0;
229 	d->nr_reg += hw->sense_regs ? hw->nr_sense_regs : 0;
230 	d->nr_reg += hw->ack_regs ? hw->nr_ack_regs : 0;
231 	d->nr_reg += hw->subgroups ? hw->nr_subgroups : 0;
232 
233 	d->reg = kzalloc(d->nr_reg * sizeof(*d->reg), GFP_NOWAIT);
234 	if (!d->reg)
235 		goto err2;
236 
237 #ifdef CONFIG_SMP
238 	d->smp = kzalloc(d->nr_reg * sizeof(*d->smp), GFP_NOWAIT);
239 	if (!d->smp)
240 		goto err3;
241 #endif
242 	k = 0;
243 
244 	if (hw->mask_regs) {
245 		for (i = 0; i < hw->nr_mask_regs; i++) {
246 			smp = IS_SMP(hw->mask_regs[i]);
247 			k += save_reg(d, k, hw->mask_regs[i].set_reg, smp);
248 			k += save_reg(d, k, hw->mask_regs[i].clr_reg, smp);
249 #ifdef CONFIG_INTC_BALANCING
250 			k += save_reg(d, k, hw->mask_regs[i].dist_reg, 0);
251 #endif
252 		}
253 	}
254 
255 	if (hw->prio_regs) {
256 		d->prio = kzalloc(hw->nr_vectors * sizeof(*d->prio),
257 				  GFP_NOWAIT);
258 		if (!d->prio)
259 			goto err4;
260 
261 		for (i = 0; i < hw->nr_prio_regs; i++) {
262 			smp = IS_SMP(hw->prio_regs[i]);
263 			k += save_reg(d, k, hw->prio_regs[i].set_reg, smp);
264 			k += save_reg(d, k, hw->prio_regs[i].clr_reg, smp);
265 		}
266 	}
267 
268 	if (hw->sense_regs) {
269 		d->sense = kzalloc(hw->nr_vectors * sizeof(*d->sense),
270 				   GFP_NOWAIT);
271 		if (!d->sense)
272 			goto err5;
273 
274 		for (i = 0; i < hw->nr_sense_regs; i++)
275 			k += save_reg(d, k, hw->sense_regs[i].reg, 0);
276 	}
277 
278 	if (hw->subgroups)
279 		for (i = 0; i < hw->nr_subgroups; i++)
280 			if (hw->subgroups[i].reg)
281 				k+= save_reg(d, k, hw->subgroups[i].reg, 0);
282 
283 	memcpy(&d->chip, &intc_irq_chip, sizeof(struct irq_chip));
284 	d->chip.name = desc->name;
285 
286 	if (hw->ack_regs)
287 		for (i = 0; i < hw->nr_ack_regs; i++)
288 			k += save_reg(d, k, hw->ack_regs[i].set_reg, 0);
289 	else
290 		d->chip.irq_mask_ack = d->chip.irq_disable;
291 
292 	/* disable bits matching force_disable before registering irqs */
293 	if (desc->force_disable)
294 		intc_enable_disable_enum(desc, d, desc->force_disable, 0);
295 
296 	/* disable bits matching force_enable before registering irqs */
297 	if (desc->force_enable)
298 		intc_enable_disable_enum(desc, d, desc->force_enable, 0);
299 
300 	BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
301 
302 	/* register the vectors one by one */
303 	for (i = 0; i < hw->nr_vectors; i++) {
304 		struct intc_vect *vect = hw->vectors + i;
305 		unsigned int irq = evt2irq(vect->vect);
306 		int res;
307 
308 		if (!vect->enum_id)
309 			continue;
310 
311 		res = irq_alloc_desc_at(irq, numa_node_id());
312 		if (res != irq && res != -EEXIST) {
313 			pr_err("can't get irq_desc for %d\n", irq);
314 			continue;
315 		}
316 
317 		intc_irq_xlate_set(irq, vect->enum_id, d);
318 		intc_register_irq(desc, d, vect->enum_id, irq);
319 
320 		for (k = i + 1; k < hw->nr_vectors; k++) {
321 			struct intc_vect *vect2 = hw->vectors + k;
322 			unsigned int irq2 = evt2irq(vect2->vect);
323 
324 			if (vect->enum_id != vect2->enum_id)
325 				continue;
326 
327 			/*
328 			 * In the case of multi-evt handling and sparse
329 			 * IRQ support, each vector still needs to have
330 			 * its own backing irq_desc.
331 			 */
332 			res = irq_alloc_desc_at(irq2, numa_node_id());
333 			if (res != irq2 && res != -EEXIST) {
334 				pr_err("can't get irq_desc for %d\n", irq2);
335 				continue;
336 			}
337 
338 			vect2->enum_id = 0;
339 
340 			/* redirect this interrupts to the first one */
341 			set_irq_chip(irq2, &dummy_irq_chip);
342 			set_irq_chained_handler(irq2, intc_redirect_irq);
343 			set_irq_data(irq2, (void *)irq);
344 		}
345 	}
346 
347 	intc_subgroup_init(desc, d);
348 
349 	/* enable bits matching force_enable after registering irqs */
350 	if (desc->force_enable)
351 		intc_enable_disable_enum(desc, d, desc->force_enable, 1);
352 
353 	nr_intc_controllers++;
354 
355 	return 0;
356 err5:
357 	kfree(d->prio);
358 err4:
359 #ifdef CONFIG_SMP
360 	kfree(d->smp);
361 err3:
362 #endif
363 	kfree(d->reg);
364 err2:
365 	for (k = 0; k < d->nr_windows; k++)
366 		if (d->window[k].virt)
367 			iounmap(d->window[k].virt);
368 
369 	kfree(d->window);
370 err1:
371 	kfree(d);
372 err0:
373 	pr_err("unable to allocate INTC memory\n");
374 
375 	return -ENOMEM;
376 }
377 
378 static ssize_t
379 show_intc_name(struct sys_device *dev, struct sysdev_attribute *attr, char *buf)
380 {
381 	struct intc_desc_int *d;
382 
383 	d = container_of(dev, struct intc_desc_int, sysdev);
384 
385 	return sprintf(buf, "%s\n", d->chip.name);
386 }
387 
388 static SYSDEV_ATTR(name, S_IRUGO, show_intc_name, NULL);
389 
390 static int intc_suspend(struct sys_device *dev, pm_message_t state)
391 {
392 	struct intc_desc_int *d;
393 	struct irq_data *data;
394 	struct irq_desc *desc;
395 	struct irq_chip *chip;
396 	int irq;
397 
398 	/* get intc controller associated with this sysdev */
399 	d = container_of(dev, struct intc_desc_int, sysdev);
400 
401 	switch (state.event) {
402 	case PM_EVENT_ON:
403 		if (d->state.event != PM_EVENT_FREEZE)
404 			break;
405 
406 		for_each_active_irq(irq) {
407 			desc = irq_to_desc(irq);
408 			data = irq_get_irq_data(irq);
409 			chip = irq_data_get_irq_chip(data);
410 
411 			/*
412 			 * This will catch the redirect and VIRQ cases
413 			 * due to the dummy_irq_chip being inserted.
414 			 */
415 			if (chip != &d->chip)
416 				continue;
417 			if (desc->status & IRQ_DISABLED)
418 				chip->irq_disable(data);
419 			else
420 				chip->irq_enable(data);
421 		}
422 		break;
423 	case PM_EVENT_FREEZE:
424 		/* nothing has to be done */
425 		break;
426 	case PM_EVENT_SUSPEND:
427 		/* enable wakeup irqs belonging to this intc controller */
428 		for_each_active_irq(irq) {
429 			desc = irq_to_desc(irq);
430 			data = irq_get_irq_data(irq);
431 			chip = irq_data_get_irq_chip(data);
432 
433 			if (chip != &d->chip)
434 				continue;
435 			if ((desc->status & IRQ_WAKEUP))
436 				chip->irq_enable(data);
437 		}
438 		break;
439 	}
440 
441 	d->state = state;
442 
443 	return 0;
444 }
445 
446 static int intc_resume(struct sys_device *dev)
447 {
448 	return intc_suspend(dev, PMSG_ON);
449 }
450 
451 struct sysdev_class intc_sysdev_class = {
452 	.name		= "intc",
453 	.suspend	= intc_suspend,
454 	.resume		= intc_resume,
455 };
456 
457 /* register this intc as sysdev to allow suspend/resume */
458 static int __init register_intc_sysdevs(void)
459 {
460 	struct intc_desc_int *d;
461 	int error;
462 
463 	error = sysdev_class_register(&intc_sysdev_class);
464 	if (!error) {
465 		list_for_each_entry(d, &intc_list, list) {
466 			d->sysdev.id = d->index;
467 			d->sysdev.cls = &intc_sysdev_class;
468 			error = sysdev_register(&d->sysdev);
469 			if (error == 0)
470 				error = sysdev_create_file(&d->sysdev,
471 							   &attr_name);
472 			if (error)
473 				break;
474 		}
475 	}
476 
477 	if (error)
478 		pr_err("sysdev registration error\n");
479 
480 	return error;
481 }
482 device_initcall(register_intc_sysdevs);
483